A group of researchers found a dinosaur that resembles Tyrannosaurus Rex a lot when it comes to its tiny forelimbs. In a research paper describing the new fossil, scientists write that Gualicho shinyae is also a two-legged dinosaurs with petty, two-fingered arms.
Paleonthologists exlained that dinosaurs belonging to the therapod family either have smaller arms or tend to change their functionality. And G. shinyae is no exception. The dinosaur was first unearthed nine years ago in Argentina, but it is the first time it gets a name and a proper scientific description in a respectable journal.
According to the paper, the animal’s forelimbs were relatively smalls compared to the rest of its body: about 2 ft long. Additionally, the hand, had poor muscle tone and weak joints, which means that they were extremely frail.
The creature’s fingers are very T .rex-like, researchers wrote, with a large claw on its thumb and a slim middle finger. There is a third finger as well, but it is so underdeveloped that it looks like a small bony growth on the dinosaur’s hand.
Lindsay Zanno of the North Carolina Museum of Natural Sciences, who hasn’t contributed to the research, said that Gualicho shinyae resembles the King of Dinosaurs with its small arms reduced to just two functional fingers.
However, Gualicho is not related to T. Rex despite similarities, researchers said. Its bone structure and skeleton suggests that it belongs to other groups of dinosaurs. Scientists are now trying to figure out why therapods have so tiny arms.
They can only speculate that the carnivorous dinosaurs didn’t need the arms to wrangle prey since their head and neck were pretty strong. The same trend is noticed in tyrannosaurs which tend to have smaller arms when their heads and bodies become more massive.
Scientists guess that in the case of the two animals, the head took over many functions of the forelimbs. However, the two groups of dinosaurs are not unique. Carcharodontosaurs and ceratosaurs are also equipped with unusually small forelimbs as they probably heavily relied on their heads when pursuing and killing prey.
Paleontologists are now trying to fit the newly found specimen into a dinosaur family as its bones suggest that it may belong to two separate groups of theropods: the Neovenatoridae and Deltadromeus. The latter group stems from Africa, which suggests that Gualicho and the African group may be closely related.
A research paper detailing the dinosaur was published July 13 in the journal PLOS ONE.
Image Source: Wikimedia